Method of and apparatus for making a sealing slide fastener having laterally curved portions



March 15, 1960 H. H. ARMSTRONG 2,

METHOD OF AND APPARATUS FOR MAKING A SEALING SLIDE F ASTENER HAVING LATERALLY CURVED PORTIONS Original Filed May 19, 1955 4 shee she t 1 IN VEN TOR. AbWHHD HHFMS THU/v5 K W HT TY.

' H- H. ARMSTRONG March 15, 1960 2,928,127 METHOD OF AND APPARATUS FOR MAKING A SEALING SLIDE FASTENER HAVING LATERALLY CURVED PORTIONS Original Filed May 19, 1955 4 Sheets-Sheet 2 INVENTOR. fiUI VHED. HI ERA/l5 THU/V5 m IN 1 llll \O% A J nw gn w wm A wwm 11K mw ||+||||I|||||||ll|||l|||||| 1||||l1||||| llll -lllll \I lllll II lllll ll I: wk B IITR Nb Q nk mh fir wwiiamww iiaiizii-1.MW-#--::N vb

March 15, 1960 H. H. ARMSTRONG 2,928,127

METHOD OF AND APPARATUS F OR MAKING A. SEALING SLIDE FASTENER HAVING LATERAL I JY CURVED PORTIONS Origingl Filed May 19, 1955 4 Sheets-Sheet s 55 87 38 as as 63 Hrrx March 15, 1960 H. H. ARMSTRONG 2,928,127 METHOD OF AND APPARATUS FOR MAKING A SEALING SLIDE FASTENER HAVING LATERALLY CURVED PORTIONS Original Filed May 19, 1955 4 Sheets-Sheet 4 uvmvron.

HUWHED HERA/5 TFUNE WZM? H 7 TY.

METHOD OF AND APPARATUS FOR MAKING A SEALING SLIDE FASTENER HAVING LATER- ALLY CURVED PORTIONS Howard H. Armstrong, Akron, Ohio, assignor to The B. F. Goodrich Company, New York, N.Y., a corporation of New York Claims. ct 18 -36) The invention relates to methods of an apparatus for making separable fasteners including slide fasteners of the sealing type having one or more laterally curved portions intermediate the ends thereof.

This application is a division of my copending application Serial No. 509,483, filed May 19, 1955, now Patent No. 2,909,823, wherein the sealing slide fastener with laterally curved portions is claimed.

Customary practice, heretofore, has been to manufacture sealing slide fasteners in pro-determined, continuous, straight lengths each havinga pair of flexible, stretchresisting attaching margins or stringers or tapes of uniform length with interengageable fastener elements or teeth in series and elastic sealing elements thereon. Such straight fasteners have been generally suitable for commercial articles and structures in general. Nevertheless, the straight length of these fasteners and the uniform length and stretch-resistance of their pair of stringers have made the straight fasteners diflicult to apply to articles and structures requiring localized lateral curvature along one or more reaches or zones or regions of such fasteners, and this has unduly limited their field of commercial and industrial applications. 3 r In some cases, for example,- the expedient of cutting suitable notches in both stringers along a reach of the straight fastener has been utilized to avoid buckling and pendent, straight slide fasteners arranged in series have been connected at their adjacent ends in an angular relation (for example, an approximately ninety degree (90) relation) to provide for their mounting along a path having one or more angular zones therein. This angular construction avoids buckling and notching of the stringers, but is expensive to make. Also,' the angular construction makes it dilficult to provide continuity of separability and sealing at said zones, and does not provide localized laterally curved reaches in the attachment as a whole. 7 i Y Y Objects of the invention are to provide for improved apparatus and methods of making a sealing slide fastener having provision of lateral curvature of its attaching margins and sealing elements along a reach of determinate length and adapted to overcome the foregoing and other disadvantages of the prior constructions; to provide for forming at least one laterally curved reach in asealing slide fastener, while maintaining the fastener in a connited States Patent ICC for producing a laterally curved construction in a reach.

of a sealing slide fastener capable of -fittin'g a limited range of differently curved paths, while avoiding notching of one or both attaching margins; and to provide for convenience .of manufacture and installation and for in," while the fastener is maintained in a continuous straight condition; to provide mold apparatus for and method of making, molding and vulcanizing a sealing slide fastener with a laterally curved reach therein having provision for conforming to a plurality of curved paths or bends each of differenfradius of curvature; to provide mold apparatus for effecting permanent set in the laterally curved attaching margins along a reach of the sealing slide fastener; and to provide mold'apparatus for molding an initiallateral curvature in a reach of a sealing slide fastener, while curingthe same, and for subsequently re-fo'rming the initially curved reach to produce a desired permanent set and a predetermined later- Fig. 1, parts being broken away,

Fig.3 is a plan view of a commercial slide fastener of the non-sealing type, parts being broken away,

folding of one stringer 'but'facilitate lengthening of the Fig. 4 is a plan view-from above of the lower half of a straight mold for. making the laterally curved, pressure-sealing slide fastenershown in Fig. 1, the lower half being arranged to show itsrnolding surface configuration, parts being broken away, i 1

Fig.5 is a plan viewfrom above of the top half of the straight mold laid back and arranged to show its molding surface configuration for making the laterally curved,

I pressure-sealing slide fastener shown in Fig. 1,1 parts being broken away, p 7

Figs. 6, 7, 8 and 9 are sectional views of the respective halves of the mold taken along lines-6.- -6, 7"7, 8--8, and 9--9, respectively, in Figs. 4 and 5, 7 Figs. 10 and 11 are side elevational views takenalong lines 1t 10 in Fig. 4 and 11--1'1 in Fig. 5 showing attaching margin or stringer-shaping means including in I sert bars for the mold, parts being broken away,

Fig. .12 is a sectional view of the lower half of the mold with a standard commercial slide fastener disposed thereon in fully separated condition preparatory to mold ing resilient rubber sealing elements upon the teeth'of the fastener, parts being broken away and in section,

Fig. 13 is a sectionalview ofthe molded pressuresealing slide fastener after removal from the mold and before'engagement of the teeth and sealing elements, parts being broken away,

Fig. 14 is a plan view of the' molded pressure-sealing slide fastener having a laterally curved reach therein tinuous straight condition; to provide for molding a I sealing slide fastener in a straight condition and in a manner effecting a permanent, laterally curved set in the attaching margins or stringers of'the fastener; to provide after 'removal from the mold and after engagement of Patented Mar. 15,

Fig. 2 is a sectional view taken along line 2- -2 in.

molded pressure-sealing slide parts being broken away,

Fig. 16 is a sectional view taken along line 1616 inFig. '15, parts being broken away, and

Fig. 17 is' a plan view from above of the molded pressure-sealing slide fastener having the re-forrned laterally curved reach after'removal from the final-shaping mold.

Window attachment construction The'automobile window attachment shown in Figs. 1 and 2 includes a continuous slide fastener 2t? of the pressure-sealing type with molded-in, spaced-apart, laterally curved reaches or portions 21, 22 therein. The improved slide fastener 20 produced by the hereinafter described method and apparatus of the invention, separably unites the two side margins 23, 24 and top margin 25 of a rear window 26 of suitable transparent, flexible plastic material with corresponding margins 27, 28 and 2? of a collapsible or foldable cover or top 39 of waterproof textile fabric or other suitable flexible, impervious wall material for an automobile 31 of the convertible type. The foldable top 30 has its bottom margin fixedly'atached by known attaching means to a body 32 of the automobile, while the bottom margin ofthe flexible rear window 26 is fixedly attached by known attaching means to a wall of the mouth of a well or storage space (not shown) in the rear of the body 32, which well is adapted to. receive thewindow and the foldable top. The junction of the Window and the foldable top with the body 32 is covered by a trim strip 33 of suitable rust-resistant metal.

The flexible rear window shown in Fig. l is generally rectangular in shape for good viewing purposes and has curved upper corners for good appearance purposes.

The pressure-sealing slide fastener 20 has fastener elements or teeth 35, 36 desirably of suitable strong metal mounted in series along each of the adjacent marginal edges including textile cord beads 3721,3842 of attaching margins or stringers 37, 38 desirably of flexible, knitted or square-woven fabric of, cotton or. nylon or other suitable textile material, which teeth are engaged and dis engaged by manipulation ofa runner or slider 39 to close and open the fastener. A pair of sealing elements 40, 41 of resilient, natural or synthetic, rubber, or other suitable elastic rubber-like material and of generally L-shape in crossfsection, may be mounted in part upon the teeth and in part upon the attaching margins or fabric stringers at a face thereof and bonded thereto, as shown especially in Fig. 2. The sealing elements in the closed i.e., engaged position have laterally overlapping outer and inner marginal portions each tapering to an edge for effecting continuity of sealing along the fastener by resilient flexure and pressing of the edge of the tapered outer marginal portion slidably against the inclined seating surface of the tapered inner marginal portion. The fabric attaching margins 37, 38 have thin, continuous sealing layers or coatings 42, 43 of suitable resilient rubberincontinuation of the rubber material of the sealing elements 40, 41.

The attaching margin or stringer 37 of thefastener 20 may be fixedly secured to the adjacent fabric margin of the automobile top 30 as byra double row of stitching 44, 44 of suitable strong, filamentary textile material or thread, and preferably a thin reinforcing tape or strip 45 of suitable rubberized, woven fabric material is disposed between the rubber surface of the attaching margin and the fabric top 30 for increased strength and sealing purposes. The other attaching margin or stringer 3% of fastener mounted. therein,

flexible, transparent rear window 26. The sealing elements 40, 41 are preferably disposed at the exterior of the automobile top 30 for good appearance and sealing purposes, while the teeth 35, 36 and the. slider. 3% are disposed at the interior. of the top 30;

This makes feasible an attractive, neatly appearing and waterproof attachment of the rear window 26 to the automobile top 3%) by the improved pressure-sealing slide fastener 26. The slider 39" can be manipulated from the interior of the top 30 so as to open the slide fastener throughout its length, whereupon the rear window as can be flexed and disposed entirely Within the Well in the rear of the automobile body 32. The rear window 26 can be conveniently lifted from within the well and quickly and easily secured in place in the rear opening in the automobile top 30 by operation of the slider 39'so as to close the slide fastener 20.

Manufacture of a laterally curved sealing slide fastener To the ends of conveniently and economically producing a continuous strip or length of pressure-sealing slide fastener 20 having at least one and preferably two laterally curved portions 21, 22, theinvention provides forming and molding apparatusshown in Figs. 4 to 12, in: clusive, and final-shaping mold apparatus shown in Figs. 15 and 16. The molding apparatus makes feasible the use of a continuous strip or length of a standard commercial slide fastener 20a of the ,nonsealing type which as manufactured and as shown in the closed condition in Fig.3, has its untreated, woven fabric (desirably cotton fabric) stringers 37, 38 initially'woven and. formed at spaced-apart positions to a desired lateral curvature of suitable radius of curvature to provide for example, a five inch radius of curvature of the centerline i.e., median line of engagement of the teeth 35, 36, which median line is indicated by the numeral 46a. The. teeth 35, 36 along the pro-formed curved portions are, in the engaged condition, inclined relative to the centerline 45a in the manner shown to promote ease of engagement of the teeth. i I

All portions of both stringers 37, 38, as manufactured, have limited longitudinal looseness so that they lie substantially fiat andsmooth in the same horizontal plane passing laterally through the'fastener 20a including its pre-formed bends or sharply curved portions. Said preformed bends maybe in excess of angularity, for example, from about to about at the centerline 46a, as shown in Fig. 3, to facilitate the desired window attachment having each bend therein slightly exceeding 90, for example, a 94 bend. The curvature of the pre-forrned bends may be in the same lateral direction to one side of the centerline 46a of the slide fastener 20a. Thus, the continuous strip of standard slide fastener 20a has a generally U-shaped configuration in plan..

Ordinary molding apparatus for accommodating and maintaining the continuous strip of slide fastener 20a in its normal U-shaped configuration, while molding the resilient rubber sealing elements on the fastener, is not only cumbersome, unwieldly and diflicult to handle, but is very expensive to make and maintain and is not suited to quantity production. The new and useful forming and molding means or apparatus shown in the drawings overcomes these disadvantages by virtue of its'straight construction and arrangement maintaining the continuous strip of slide fastener 26a in a continuous straight line condition and in open or separated condition, while molding the rubber sealing elements on the slide fastener Ztla, all without destroying the initial or pre-formed lateral curvature of the fabric stringers at the spaced-apart laterally curved reaches in the slide fastener 20a.

M ola'z'ng apparatus nswer,

shown has a single strip capacity and. includes a twopiece, straight mold 50 of the desired length and other dimensions and of suitable metal such, for. example, as aluminum alloy, cast iron, steel or other hard metal resistant to objectionable warping and .deformation at the temperatures and pressures generally used for vulcanizing elastic rubber compositions. The mold 50 is preferably made of aluminum alloy for ease of handling, and has an elongated lower half or mold plate 51, shown molding surface up in Fig. 4, and has an elongated .upper half or mold plate 52, shown in Fig. laid back and molding surface up relative to the lower half 51.

The lower mold plate 51 has a lower supporting surface 53 for disposition upon a suitable curing press platen (not shownland an elongated upper molding surface 54 which is. flat throughout the major portion thereof and lies in a single horizontal plane and desirably extends continuously the full length of the lower mold plate. An upraisedor outwardly projecting, separating rib or ridge 55 of suitable narrow, uniform width extends centrally along a straight path in the molding surface 54 intermediate its side margins and continuously from end to end of the mold plate 51, thereby dividing the molding surface lengthwise or longitudinally into two individual, stringer-supporting, side surface areas 54a, 54b.

Shallow, straight teeth-receiving channels or grooves 56, 57 in the molding surface 54 aredisposed immediately at the two sides of the separating rib 55 and extend unobstructed, continuously and in parallel relation'from end to end of the mold plate 51. The shape, uniform depth and width of each shallow channel or groove 56, 57 are sufficient to accommodate snugly the lower parts of the teeth of the fastener, when the fabric stringer is lying. flushtagainst the adjacent molding surface 54. The uniform height to which the separating rib 55 projects above the horizontal plane of the molding surface 54 issuflicient to position the flat upper face of the separating rib in the horizontal plane of the upper faces of the teeth, when the teeth are seated in the-grooves 56, 57 and the fabric stringers 'lie flush against the adjacent molding surface 54, as shown in Fig. 12. s

The two sides of the lower mold plate 51 at its upper molding surface 54 are cut-away to provide suitable shaped side recesses 58, 59 for mold-register and locking purposes. A suitable extension 60 with upright dowel pin to equal the width of the fabric stringer and, to entirely underlie'and fully support a pre-formed, laterally curved reach or portion in the fabric stringer (for example, outer stringer 37), when the teeth of the stringer are seated in thegroove 56.' The said fabric stringer (37) has a greater radius of curvature than that of the other (inner) stringer (38) of the fastener 20a. The =side marginal edge 67 of the forming surface i.e., contoured smooth surface and end surfaces 65, 66 is closely spaced (for example, about 0.025") from the sidewall in the groove 56 and is continuously straight and lies throughout its entire length in the horizontal plane of the adjacent flat molding surface 54. The otherv side marginal edge 68 of the forming surface i.e., the contoured smooth surface and end surfaces 65, '66is continuously straightv as viewed from above, but rises and falls sinuously in level along its contoured surface length between positions D-D relativeto the horizontal plane of the adjacent flat molding surface 54.

The contoured smooth surface between position D-D has a plurality of interconnected, substantially;uniform undulations extending laterally of said surfacebetween the side marginal edges 67, 68,- and providing a rhythmic succession of rounded wave-like crests 69, 69--and hollows 70, 70, as shown in Fig. 10, to accommodate and shape the fabric stringer 37 without producing objectionable local- 61 projects from an end of the mold plate 51 to facilitate insertion of the dowel pin through an aperture in end extension 62 of the upper mold plate 52 for further registering and locking the mold plates. 7

The molding surface 54 of the lowerfmold plate 51 has at least one stringer-shaping means 63 andfor the particular, mold shown in the drawings, 'has a second stringer-shaping means 64. Each means 63, 64 is located .in the side surface area 54a of the molding surface 54 to a side of the separating rib 55, and is adjacent and closely spaced from the sidewall of the teeth-receiving groove 56 remote from the separating rib 55, as shown especially in Fig. 8. Each means 63, 64 is located at a position lengthwise of the molding surface 54 corresponding to. the desired lengthwise position of a laterally curved reach or portion in the molded sealing slide fastener strip 20, and also corresponding to the lengthwise position of a pre-formed, laterally curved reach or portion in the standard commercial slide fasten,- er 20a.

ized wrinkles and ta'utness.v The rounded crests 69, 69 rise above the level of both the straight, planar. side marginal edge '67 and the adjacent fiat molding surface 54, and the rounded hollows 70, 70'fall below the level of. both the straight, planar side marginal edge 67 and the adjacent flat molding surface 54. Beginning at the planar side marginal edge 67, the uniform hollows 70, 70increase gradually in depth toward the opposite edge' 68 pai't way across and desirably across at least one-half the ,width of the contoured smooth surface, and thereafter are of substantially uniform height, and depth, respectively, to said opposite or other side marginal edge 68. This advantageously avoids producing undue localized stretching and straining of the material of. the fabric stringer while accorhmodatingthe latter during the molding operation: y a

' The theoretical overall length of the contoured smooth surface from position D to position D, as measured in the plane of the flat molding surface 54, must be at least equal to and is established by the arcuate extent of a particular laterally curved portion of the desired radius of curvature in themolded sealing slide fastener 20, as measured along the centerline, that is, the median line as of engagement of the teeth of the fastener. However, the theoretical overall length may also be established by the arcuate length (from position A to position A) of the centerline or median line 46a along the particular laterally curved portion in the standard commercial slide fastener 26a shown inFig. 3. This arcuate a length between the positions AA in the centerline 46a The stringer-shaping means 63, 64 each has a rigid forming surface comprising an elongated, contoured smooth surface extending longitudinally of the molding surface 54' in a straight path from position D to position D, and desirably comprising narrow, flat end surfaces 65, 66 in continuation of the contoured smooth surface and merging smoothly with adjacent planar portions of the molding surface 54, as shown in Fig. 4. The forming surface i.e., the contouredsmooth surface and end surfaces 65, 66 hasv a substantially uniform widthsuflicient approximately corresponds to that .of the centerline' of the laterally curved portionin the molded sealing slide fastener 20. The said theoretical overall length of the contoured smooth surface establishes the theoretical length of the straight, planar side marginal edge 67 between positions D-'D, and must be at least equal to said arcuate length between the positions A. A. It 'is to be noted that the theoretical length D-D of the marginal edge 67 substantially'equals the arcuate length of the inner beaded edge 37a of the fabric stringer 37 in its curved reach between the positions AA at the centerline 46a.

The substantially uniform undulations are of sufficient number and dimensions to provide a theoretical overall length of the vertically sinuous side marginal edge 68 between positions D-D, as measured conformingly along the curvature of the rounded crests and hollows, corresponding to at least the greatest arcuate length in the outer stringer 37 J v the laterally curved portion of the agoesiiar 7 slide fastener zila, that is', thearcuate length of the outer marginal edge of the fabric stringer 37 from position B- to position B therein. The construction and arrangement provides sufiicieut' length of the contoured smooth surface, measured longitudinally from any position across its width, to accommodate all the material ofa curved reach in the fabric stringer 37 without objectionable wrinkling and stretching of the same, when the stringer toured smooth surface required to produce a laterally.

curved portion having a particular radius of curvature,

is established in part by the shortest arcuate length of a curved reach of the outer stringer 37 as measured along the centerline 4611 from position A to position. A, and is established in part by the greatest arcuate length of the curved reach of the outer stringer 37 as measured from position B to position B along the outer marginal edge of the stringer as shown in Fig. 3.

From the standpoint of practical manufacturing prac tice, it has been found that the theoretical overall length of the contoured smooth surface audheuce the said form: ing surface of means as, '64, must be increased a suitable amount so that'the actual overall length of'the contoured smooth surface fromposition D to position D equals'a certain surplus length .plus' the said theoretical overall length. This actual overall length is preferably sufficient to accommodate standard manufacturing tolerances in the spacing and size of the teeth and in. the looseness of weave and fullness of'material of the fabric stringer 37 of the commercial slide fastener. Zita, and also sufiicient to accommodate limited longitudinal shiftingand local ized working (shortening and/or lengthening) of the fabric stringer 37, while'it is being mounted upon the mold plate 51. The actual overall length of the contoured smooth surface varies not only'with the desired arcuate length of each laterally curved portion in the molded slide'fastener and fullness of material in the laterally curved part of the outer stringer, and with the desired total length of the continuous strip to be produced, but also varies with the longitudinal spacing between the laterally curved portions and the particular construction of the fabric stringers in the commercial slide fastener Ella. Thus, theactual overall length of the contoured smooth surface has provision for accommodating a length of the outer stringer substantially in excess of the arcuate length of either marginal edge in the outer stringer at the laterally curved portion in the commercial slide fastener Zita, whereby a contoured or undulated length of the molded outer stringer (see 'Fig. 14) is produced which exceeds that required by the laterally curved reach in the commercial slide fastener 29a.

This increased undulated length of the molded outer stringer assures obtaining the desired lateral bend (for example, about 100) having the designed radius of curvature (for example, radius) of the centerline 46, when the molded slide fastener 25) is conformed and bent laterally during its attachment to the structures to be joinedie, the automobile top and the rear window. It permits limited longitudinal shifting of the center of radius of curvature of the centerline 4-6 of the laterally curved portion in the molded slide fastener 20. It facilitates fitting the said laterally curved portionto a centerline radius of curvature which can be slightly less (for example, about 4 radius), or can be substantially greater (for example, about 7 radius) than the designed radius of curvature (for example, 5" radius).

A suitable practical forming surface of each means 63, as for accommodating and shaping the laterally curved portion of the outer stringer 37 of the commercial slide fastener 29a having a designed lateral bend of about 160 and radius of. curvature of 5 of theceuterline 46a, may

have the followingdimensions, although: not necessarily' The Width of the forming surface limited thereto. throughout is 01756" from flat'marginal edge 67 to contoured marginal edge 68; The entire actual length-of the forming surface from end to end thereof, as. measured along the straight, fiat marginal edge 67 in the horizontal plane of the molding surface 54, is 11.798". Each narrow, fiat end surface as, so of the forming surface is 9.259" measured along the marginal edge 67.

The contoured smooth surface, between positions D-D, has an actual overall length of H.298" measured along the straight, fiat marginal edge 67, and has 21 undulations in which each crest 6%, 69 and each hollow 7%, if is of 0.381" radius and is of 0.111" maximum height above or below the level of the straight marginal edge 67. The horizontal distance from the centerline of one crest 69 to the centerline of the adjacent hollow 73 is 0.538". The theoretical overall length, however, of the contoured smooth surface is 8.840" as established by the arcuate length of the centerline 46a along its 100 curve or bend with a 5" radius of curvature betweenpositions A-A in the commercial slide fastener 20a. The difference between the actual overall length of H.928 and the theoretical overall length of 8.840 amounts to 2.453 length provided for. the purposes discussed hereinabove.

For convenience of manufacture and servicing-of the.

mold, the forming surface of each stringer-shaping means 63, 64 is provided by the shaped upper face of an elongated insert bar 71, 71 of aluminum alloy, steel or other suitable metal which is rigid and resistant to distortion under the temperatures and pressures encountered in vulcanizing rubber. As shown in Figs. 4 and 8, the elongated insert bar. 71 is disposed and press fitted in a suitable recess in the lower mold plate 51, whereby the bar is firmly supported against movement and has the straight, planar side marginal edge 67 in the plane of the molding surface 54 and has the crests 69, 69 and hollows 7d, 7%, respectively, rising and falling above the plane of the molding surface 54}. V

The molding surface 54 of the lower mold plate 51 at its fiat planar area 54b to the other side of the separating rib 55 does not require additional stringer-shaping means for the other or inner fabric stringer 38 of the fastener 26a, but is continuously flat and planar from end to end and from the teeth-receiving groove 57 to the side recess 5?. When the teeth 36, 36 of the inner fabric stringer 33 are seated in the groove 57, the continuously fiat, planar molding surface 554 at its side area 5% entirely underlies V the fabric stringer 38 including its straightened curved reaches for supporting the same, whereby during the molding operation the fabric stringer is maintained and formed and shaped flat and planar throughout, its entire width and length, the limited surplus and the give of the fabric material facilitating this result even though localized tautness resulting in limited narrowing of the fabric may be present at the straightened curved reaches. Objectionable wrinkles and stretching in the stringer 38 are avoided.

The upper mold plate 52 of suitable metal such, for example, as aluminum alloy is constructed and arranged to fit superimposed upon the lower mold plate 51 and has a suitable upper face 52a as for contacting the upper platen of a suitable curing press (not shown). The upper. mold plate 52 has its opposite or lower face (shown uppermost in Pig. 5) constituting a fiat, planar molding which is the increased or surplus margins inwardly of the projections 73, 74 for accommodating overflow of the rubber material during the molding and vulcanizing operation.

The molding surface 72 has a pair of continuous molding grooves 77, 78 of suitable shape in cross-section and dimensions extending spaced-apart and parallel and cmtrally therein from end to end thereof for directly overport or table (not shown). The continuous strip of standard commercial slide fastener a of the nonsealing type having the spaced, pro-formed laterally curved lying the teeth-receiving grooves 56, 57 in the lower mold plate 51 and for shaping and molding thecontinuous, resilient rubber, sealing elements 40, 41 in part upon the teeth 35, 36 and in part upon the fabric stringers 37, 38, as shown in Figs. 2 and 13. Between the molding grooves 77, 78 for the sealing elements extends a fiat spacer face 79 having a narrow, shallow, continuous recess .86 therein for rubber overflow purposes, the spacer face 79 being adapted to directly overlie the upraised separating rib 55 inthe lower mold plate 51; for facilitating the provision of a thin connecting web of rubber between the sealing elements during the molding operation. I

This construction and arrangement provides side areas 72a and 72b in the flat molding surface 72 substantially corresponding to and adapted to overlie the related side areas 54a and 5421, respectively, of the flat molding surface 54, when the upper 52 and lower 51 mold plates are superimposed for the molding operation,'sufficient clearance being provided between the surfaces 54, 72 to avoid objectionable pressure upon the fabric stringers yet facilitate flow of rubber across a face of the stringers. The upper mold plate 52 in its side area 72a has. a pair of stringer-shaping means 83, 84 comprising suitableelongated insert bars 81, 81 mounted and press fitted in suitable elongated recesses in the upper mold plate as shown in Fig.9. The insert bars 81, 81, for the particular embodiment shown, are alike in construction. They are located at longitudinally spaced-apart positions in the molding surface 72, as shown in Fig. '5, corresponding to the spaced-apart positions of the insert bars of the means 63,

. 64 in the molding surface 54, and are located contiguous to a side of the molding groove 78, so that they are di-.

rectly overlying and registering with the insert bars of means 63, 64 in the molding-operation.

The insert bars 81, 81 have shaped upper faces exposed at the molding surface 72 providing suitable, similar, rigid forming surfaces comprising the third and fourth stringershaping means- 83 and 84, respectively. The forming surface of the means 83, for example, comprises a suitable elongated, contoured or undulated smooth surface intermediate suitable narrow, flat end surfaces which merge smoothly with adjacent planar portions of the molding surface 72. All the dimensions of each forming surface such, for example, as that of the means 83, correspond to those of the forming surface of the means 63, but the contoured or undulated smooth surface of the means 83 has its rhythmic succession of rounded wavereaches therein is arranged in fully separated condition of the fabric stringers 37, 38 and teeth 35, 36 by virtue of known manipulation of the slider or runner 39, thereby permitting the temporary straightening of both stringers 37, 38 continuously throughout their length.

The outer fabric stringer 37 is placed and-retained in a straight condition upon and along the flat molding surface 54. at its side area 54a, and the lower parts of all the teeth 35, 35 are inserted, seated and retained in the straight teeth-receiving channel 56 in thelower mold plate 51, as shown especially in Fig. 12, so that the upper faces of all the teeth 35, 35 are flushwith i.e., in the same horizontal plane as the flat upper face of the separating rib 55. Such placement of the outer fabric stringer 37 audits teeth 35, 35 is done in a manner to dispose all the material of each preformed laterally curved portion of the stringer 37 in a temporarily straight, loose condition," that is, a ruffled disposition upon and overlying one ofthe undulating forming surfaces of the spaced stringer-shaping means 63 and 64. It has been found that generally some localized longitudinal shifting and lo calized smoothing and working i.e., stretching, or shortening, or bothQof the fabric material of the stringer 37 are required along the normally straight regions of the stringer, especially the straight region between the spaced-apart laterally curved portions thereof, so that allthe fabric material of each said curved portion in the temporary, ruffled, straight condition lies wholly within the spacedapart end boundaries of one of said undulating forming surfaces and overlies thelateral undulations in the forming surface.- This localized shifting and Workiugmakes flat molding surface 54 at its other side area 54b, and

like crests 85, 85 andhollows 86, 86 constructed and arranged for disposition in complementary relation to fabric stringer 37 into continuous conformance with the surface portion thereof of the means 63 during the molding operation. 7 7

Method steps The molding apparatus 51, 52 is designed foruse in effecting the method aspects of the invention. The upper 52 and lower 51 mold plates are separated and disposed molding surfaces 72, 54 uppermost upon a suitable supf rigid forming surface including the undulated smooth shapingmeans 63 and 64, respectively. The give and" local stretchability of the fabric material of the stringer 38 facilitates the temporary straightening with localized narrowing of the stringer.

A thin, flexible shield 87 of suitable metal is next positioned directly upon the separating rib 55 and the upper faces of the teeth 35, 35 and 36, 36 and oyer'only the engaging portions of the teeth, as shown, especially in Fig. 12, and a suitable adhesive may, if desired, be painted on the exposed upper and outer end faces of the mounting portions of the teeth 35, 35 and 36, 36, and on upper faces of the fabric stringers 37 and 38 for promoting the adhesion of rubber composition to all such exposed faces. The shield 87 bridging the engaging portions of the teeth desirably overlies in part the beaded marginal edge 37a, 38a of each fabric stringer 37, 38, so that both said edges together with the shield 87 function as a dam against the penetration of rubber composition between the teeth at their engaging portions. An extruded strip 88 of suitable unvulcanized, resilient rubber. composition for providing the desired elasticflexibility of the sealing elements, is then positioned along. and overlying the shield 87, the exposed mounting portions of the teeth 35, 35 and 36, 36 and desirably in part the portions of the fabric, stringers 37, 38, closelyadjacent the teeth. The rubber strip 8813a;

ome

sufli'cient material to at least form'thesealing elements 40, 41 and provide a thin, continuous sealing layer or coating 42, 43 of rubber upon the upper face of each stringer.

The next step is to close the mold apparatus by mounting the upperv mold plate 52 upon the lower mold plateSTl with their flat molding surfaces 54 and 72 in registered, superimposed, face toaface relation,- while the side projections '73, 74 of the upper mold plate are seated matingly in the side recesses 53, 59 of the lower mold plate 51, and while the stringer-shaping means 83, in the upper mold plate directly overlie the stringershaping means 63, 64 in the lower mold plate. The closed mold'apparatus is disposed between the platens of a known type of curing press (not shown) and the contained slide fastener Zlla and rubber strip 88 subjected wheat and pressure sufiicient to vulcanize and fully cure the rubber composition andintegrally unite the fabric and rubber parts of the slide fastener, and to form the rubber sealing elements of the desired shape and bond the same to the teeth. it is be noted that this also produces a. very thin web of rubber composition between theshield 87 and the flat, recessed, narrow face 79 in the upper molding plate 52, which web extends between and is joined to the tapered marginal portions of the spaced-apart sealing elements 40, 41 of the slide fastener when the latter is removed in its as molded condition from the opened mold apparatus.

During this phase of the molding operation, the flat planar areas of the superimposed molding surfaces 54, 72 apply sufficient pressure to the fabric stringers 37, 38 to iron out any wrinkles and distribute any looseness in the normally straight reaches of the stringers. and to maintain the stringers in a straight flat condition, while the thin, continuous sealing layers 42, 43 of rubber are formed upon and bonded to the faces of the stringers; This advantageously avoids objectionable wrinkles, nonuniformity in thickness of the sealing layer, and other molding surfaces 54, 72 directly opposite the respective stringer-shaping means press'and flatten the relatively taut, narrowed and straightened reaches of the-inner fabric stringer 38 at its pro-formed laterally curved portions without destroying the pre-formed lateral curvature of the stringer, the give of the fabric facilitating such flattening. r At the same time, the forming surfaces including the lateral undulations therein of the stringer-shaping means 83, 84' in the upper mold plate 52 press the surplus material and the straightened reaches of the outer fabric stringer 37 at its pre-formed laterally curved portions into full, smooth and mating conformance with thetunderlying forming surfaces including the lateral undulations therein of the stringer-shaping means 63, 64 in the lower mold plate 51. This is accomplished without destroying the pre-formcd lateral curvature of the stringer and without producing objectionable stresses and wrinkles in the contoured lengths of the stringer 37 along the stringer-shaping means, by virtue of the give and the surplus of fabric material along the respective stringershaping means, and by virtue of the particular construction and arrangement of jthe undulated formingsurfaces. Thus, the molding and shaping of the sealing elements 4%, 4], and the forming of the thin continuoussealing layersZ, 4-3 upon both the fabric stringers 2 7; are done while both stringers including their spaced, laterally curved'portions are maintained in a straight line. At the end of the curing period, the mold apparatus is removed from the curing press and then opened by liftingthe upper mold plate 52 entirely away from, the lower mold plate 51. Both: rubber coated fabric stringers137, 38 and their" associated'teeth 35, 36' together with their molded. rubber, web-connected sealing-elements 40, 41 and the-shield 87 between the web and the teeth, are stripped as a unit from the lower-mold plate 51, after which stripping operation the'shield 87 is next removed and then the rubber connecting web is severed from the tapered marginal portions of the molded rubber sealing elements, whereby the molded slide fastener is in the fully separated condition shown in Fig. 13.

The teeth 35, 36 of the molded slide fastener 20 may next be engaged by suitable manipulation of the slider 32 so as to join detachably the fabric stringers 37, 33 and draw the tapered marginal portions of the'sealing elements 40, 41 into overlapping contacting engagement,

thereby placing the molded slide fastener 20 in the closed condition shown in Fig. 14. Preferably, anyfiash i.e., excess rubber is trimmed from the outer marginal edges of the rubber coated fabric stringers 37, 38.

' After removal of the molded slide fastener 29 from the mold apparatus and upon subsequent engagement of the teeth, the straight molded, laterally curved portions of the fabric stringers 3'7, 38 have an inherent elastic recovery due in part to their said preforming and in part to relief of'the stresses in the fabric material, especially tension stresses in that of the inner stringer 38, whereby the molded, laterally curved portions assume, as shown in Fig. 14, a sharpness'of curvature approximately one-half that of the preformed laterally curved portions of the slide fastener 20a shown in Fig. 3. The inner fabric stringer 3S retains a generally fiat smooth condition at its curved reaches, but the outer fabric stringer 37 retains a relativeture, especially when the stringers can be separated and individually fitted to the structure to be closed by the fastener 20, and also makes feasible limited shifting of the center of radius of. curvature longitudinally of the molded slide fastener 26 as may be necessary for some applications of the fastener. I

However, for some applications the individual fitting and shaping of the molded fabric stringers to a particular curve is undesirable for cost and other reasons, in which case the molded slide fastener 20 may again be subjected to heat and pressure for a limited time, while the laterally curved portions -of the fastener are maintained at the desired exact or slightly sharper curvature for a particular installation, whereby the laterally curved portions-of the fastener are provided with a permanent set of the fabric and rubber parts, so that said curved portions retain the exact curvature required. Of course, this slightly over cures the rubber composition, hence a suitable rubber composition capable of withstanding limited overcure is used. 7

F hull-shaping mold apparatz ts The desired permanent ,set of the laterally curved portions of the molded slide fastener 26 can be conveniently accomplished by-use of the final-shaping mold apparatus, shown in Figs. 15 and 16, comprising upper 9i and lower M mold plates of suitable metal having fiat, planar molding surfaces 92 and 93, respectively, adapted to be ranged in superimposed, face-to-face relation. The molding surface 93' of the lowermolcl plate 91 has a forming groove 94 of generally rectangular shape in cross-section with oppositely inclined sides extending therein along an arcuate path and having dimensions suflicient to accommodate the sealing elements 4f), 41 in their overlapping contacting relation for the closed condition of the molded slidefastener 2t) and when the latter is inverted with the fabric stringers 3'7, 38'resting flush again"... the molding surface 93. The forminggroove 59d have straight portions in continuation of its arcuate portion. The position of'the centerline 94a of the forming groove correspondsto the position ofthe centerline or median line 46 of engagement of the teeth 35, 36 of the fastener "13 20, and the centerline 94a along the arcuate portion, of the forming groove 94 has a radius of curvature corresponding or substantially corresponding to the desired exact radius of curvature of the centerline 46 of the molded slide fastener 20 in its final-shaped, permanent set condition. The length of the arcuate portion of the forming groove 94 is sufficient to provide the desired arcuate length of a permanently set, laterally curved portion of the molded slide fastener 20 as measured along its centerline 46. The lower mold plate 91 has a plurality of metal retaining or guide pins 95,-96 secured in and projecting upwardly from its molding surface 93, the guide pins being disposed in series and spaced-apart along arcuate lines radially spaced from the sides of the forming-groove 94 so that one series of guide pins 96, 96 is at the outer marginal edge of one stringer 37 and the other series of guide pins 95, 95 is at the outer marginal edge of the other stringer 38, when the slide fastener 20 is positioned upon the molding surface 93 and in the forming groove 94 as shown in Figs. 15 and 16. The guide pins 95, 96 are received in suitable openings 97, 98 in the molding surface 92 of the upper mold plate 90, and function to retain the fabric stringers in the desired lateral curvature during the Y final-shaping operation. Y

rectly overlie and extend along a path correspondingto that of the forming groove 94. In the operation of thefinal-shaping mold apparatus, the upper 90 andlower 9l mold platesare separated; and then-themolded slide fastener 20 in its, as molded condition but with the sealing elements 40, 41 and the teeth 35, '36 engaged asshown in Fig. 14, is mounted inverted upon the flat molding surface 93 of the lower mold plate so that the engaged sealing elements 40, 41 are seated in and extend conformingly along the forming groove 94,.

While the laterally curved portions of the fabric stringers 37, 3.8 abut the molding surface 93 to the sides of the form of guide pins 95, 96 and are retained in the desired arcuate curvature by the guide pins 95, 96. Next, the upper mold plate 90 is superimposed upon the lower mold plate 91 and the supported slide fastener 20 so that the guide pins 95, 96 extend into the openings 97, 98 whereby the finalshapingmold apparatus is in its closed condition for placing in the curing press. Theclosedmold apparatus having the molded slide fastener20 therein is mounted in the curing press and the molded slide fastener thensubjected to heat and pressure for a limited time such, for example, as about minutes.- This irons or presses out any'waviness and eliminates looseness in the outer fabric stringer 37 at its curved-reach and maintains both fabric stringers 37, 38 fiat and in the desired exact lateral curvature, while effecting a permanent set in the fabric and rubber parts of the molded slide fastener 20, all without producing objectionable wrinkles in the weakening of the fabric stringers 37, 38.

At the end of the over-cure period, the mold apparatus is removed from the curing press and is opened, whereupon the molded slide fastener 20 in its final-shaped, en gaged condition is stripped from the lower'mold plate 91. The fabric stringers and the sealing elements retain the desired exact lateral curvature established by the finalshap ing mold apparatus, and resisfreturn to a greater radius of curvature by virtue of the permanent set produced in the fabric and rubber parts by'the slight overcure and second application of pressure. The molded spears? 14 slide fastener 20 in its final-shaped, permanent se't condition is shown'in Fig. 17.

Variations may be made without departing from the scope of the invention as it. is defined in the following claims.

I claim:

1.' The method of making ag-sealing slide fastener of predetermined length having a laterally curved portion therein, Which method comprises the steps of placing and ing groove and between the opposed, spaced-apart series maintaining a pair of coextensive flexible attaching margins of a slide fastener of predetermined length in a laterally spaced-apart side -by-side substantially straight condition with the materialof one attaching margin along a reach therein maintained in arufiied disposition and with thernaterial of the other attaching margin maintained in a taut disposition along a reach therein corresponding to but opposite the first said reach, said attaching margins having spaced-apart slide fastener elements including engaging portions thereof in series along adjacent spaced edges of the margins, supporting a continuous strip of vulcanizable rubber composition in a substantially straight condition in adjacent overlying relation to both series of slide fastener-elements while isolating the rubber strip from the spaces between adjacent engaging portions of all said fastener elements, and applying heat and pressure to said rubber strip in a manner to vulcanize and form therefroma pair of elastic sealing elements attached to said attaching margins respectively. 1

2. The method of making a sealing slide fastener of predetermined length having a-laterally curved portion therein, which method comprises the steps of supporting and maintaining a pair of coextensive flexible attaching margins of a slide fastener of predetermined length in a laterally spaced-apart side-by-side substantially 7 straight condition upon a rigid molding surface including both flat and undulating portions thereinand with the material of one attaching margin along a reach therein arranged in aruffled disposition in overlying relation to an undulating portion in said molding surface and with the material of the other attaching margin arranged in a taut disposition along areach therein corresponding to but opposite the first said reach and overlying a flat portion in said molding surface, said attaching margins having spaced-apart slide fastener elements including engaging portions thereof mounted in series on the margins at adjacent spaced edges thereof, supporting a continuous strip of vulcanizable rubber composition in a substantially straight condition in adjacent overlying relation to both series of slide fastener elements while isolating the rubber strip fromv engaging portions of all said fastener elements, pressing said attaching margins against and into conformance with said molding surface, and applying heat and pressure to said'rubber strip in a manner to vulcanize and margins of a slide fastener of predetermined length in a laterally spaced-apart side-by-side substantially straight condition upon a rigid molding surface including both flat and undulating portions therein, arranging and retaining the material of one supported attaching margin along a reach therein in a ruflled disposition within the boundaries of and in overlying relation to an undulating portion in said molding surface, arranging and retaining the material of the other supported attaching margin in a taut condition alonga reach therein corresponding to but opposite the first said reach and in overlying relation to a flat portion in said molding surface, said attaching margins having spaced-apart slide fastener elements each including an engaging portion and a mounting portion mounted inseries on the margins at adjacent spaced edges thereof,

15 V placing a shield overboth series of fastener elements at a face thereof and at the engaging portions thereof with the margins of the shield at saidedges ofthe supported attaching margins, molding a pair of sealing elements of elastic material against the respective series of fastener elements at said mounting portions thereof and against said shield, pressing said attaching margins against and into full smooth conformance with said molding surface, and removing said shield leaving the sealing elements against said fastener elements at said mounting portions and overlying the fastener elements at said engaging portions in unattached relation thereto.

4. The method ofmaking a sealing slide fastener of predetermined length having a laterally curved portion therein, which method comprises the steps of placing and maintaining a pair of coextensive flexible attaching margins of predetermined length in a laterally spaced-apart side-byside substantially straight condition upon a rigid molding surface including both flat and undulating portions therein, arranging and retaining the material of one supported attaching margin along a reach therein in a rufiled disposition. Within the boundaries of and in overlying relation to an undulating portion in said molding surface, arranging and retaining the material of the other supported attaching margin in a taut condition along a reach therein corresponding to but opposite the first said reach and in overlying relation to a flat portion in said molding surface, said attaching margins having spacedapart slide fastener elements each including an engaging portion and a mounting portion mounted in series on the margins at adjacent spaced edges thereof, molding a pair of sealing elements of elastic material against the respective series of fastener elements at said mounting portions thereof and restraining flow of the material of said sealing elements into the spaces between adjacent fastener elements at said engaging portions thereof by positioning a shield over said engaging portions and adjacent said edges of the attaching margins, molding a thin continuous layer of elastic material upon each attaching margin in continuation of the sealing element thereon, and removing the said shield leaving said sealing elements against said fastener elements at said mounting portions thereof.

5. The method of molding'a sealing element upon a series of spaced slide fastener elements each including an engaging portion and a mounting portion at a marginal edge of a flexible stringer having therein a pre-formed laterally curved portion along a reach thereof, which method comprises the steps of placing and maintaining said flexible stringer in a substantially straight condition including arranging and retaining the material of said stringer at said pro-formed laterally curved portion therein in a ruffled disposition along a straight path, molding a sealing element against said slide fastener elements at said mounting portions and against said stringer and restraining fiow of the material of said sealing element into spaces between the fastener elements at said engaging portions by positionin removable material across said spaces between said engaging portions in abutting relation to said marginal edge of said stringer, and removing'said removable material from across said spaces between the fastener elements leavingthe sealing element against said mounting portions and said stringer.

6. The method of molding a sealing element upon a series of spaced slide fastener elements each including an engaging portion and a mounting portion at a marginal edge of a fabric stringer having therein a preformed laterally curved portion along a reach thereof,

which method comprises the steps of supporting and maintaining said fabric stringer in a substantially straight condition upon a rigid molding surface having both fiat and undulating portions therein and arranging and retaining the fabric material of said stringer at said pro-formed laterally curved portion therein in a rufiled disposition along a straight path and overlying an undulating portiondn said molding surface, molding a sealing element againstsaid' slide fastener elements at said mounting portions and against said stringer and restraining flow of the material of said sealing element into spaces between the fastener elements at said engaging portions by positioning a shield over said engaging portions with the margin of the shield at said marginal'edge of the stringer, pressing the rufiied material of said stringer against and into full smooth conformance with said undulating portion of the molding surface and molding a thin layer of impervious flexible material in continuation of said sealing element along the stringer and upon the said ruflled material of the stringer while it is so conformed to said undulating portion, and removing said shield leaving an engaging portion and a mounting portion at a marginal edge of a fabric stringer having therein at least a'pair of spaced-apart pre-formed laterally curved portions and a straight portion therebetween, which method comprises the steps of supportingand maintaining saidfabric stringer in a substantially straight condition upon a rigid molding surface having both fiat and undulating portions therein and arranging'and retaining the fabric material of said stringer at said spaced-apart preformed laterally curved portions in a ,rufiied disposition along a straight path and within the boundaries of and overlying spaced-apart undulating portions in the molding surfacev and with he said straight portion of the stringer therebetvveen in overlying relation to said fiat portion inthe molding surface, molding a sealing element of resilient rubber material against said stringer at said mounting portions of the fastener elements, pressing the fabric material of said stringer at its straight portion against and into smooth conformance with said fiat portion in the molding surface and pressing thertiffled material'of said stringer at its spaced-apart straightened curved regions against and into full smooth conformance with said spaced-apart undulating portions in the mold ing surface, and molding a thin layer of impervious flexible rubber material in continuation of said sealing eles ment along the stringer including the rufiied and straight material'thereof while it is so conformed to said undulating and flat portions in the said molding surface, and removing'said stringer and fastener elements and sealing element and layer from said molding surface.

8. The method of making a sealing slide fastener oi prederrnined length having a laterally curved reach therein of predetermined radius of curvature at the median line of engagement of slide fastener elements each including'an engaging portion andi'a mounting portion mounted in series on adjacent edges of textile fabric stringers of said fastener, which method comprises the steps of supporting and maintaining a pair of coextensive textile fabric stringers including pre-formed laterally curved portions thereof at said reach of the fastener in a laterally spaced-apart side-by-side substantially straight condition upon a rigid molding surface including both fiat undulating portions therein and with slide fastener elements on the stringers disengaged one from the other, arranging and retaining the fabric material of one stringer alongits straightened laterally curved portion therein at said reach of the fastener in a rufiied disposition in overlying relation to an undulating portion in said molding surface, arranging and retaining the fabric material of the other stringer in a taut condition along its straightened laterally curved portion therein at said reach of the fastener and in overlying relation to a fiat portion in said molding surface, molding and vulcanizing a pair of sealing elements of resilient rubber against said stringers respectively at said mounting portions of and in overlying relation to said engaging portions of said-slide fastener elements, pressing vthe fabric stringers into full smooth conformance with said molding surface and molding and vulcanizing a thin layer of resilient rubber upon each conformed fabric stringer in continuation of the sealing element thereon, removing the assembly of fabric stringers, fastener elements, sealing elements and layers from said molding surface, uniting the molded fabric stringers by engaging the fastener elements and the sealing elements, returning the straightened laterally curved portions of said stringers partially to said radius of curvature by virtue of said engagement of the fastener elements and the elastic recovery of the fabric and rubber materials of the molded stringers at the rufiied and the taut regions respectively therein, retaining the molded united slide fastener at its laterally curved reach upon a second rigid flat molding surface with the molded sealing elements and the fabric stringers having said layers thereon extending in concentric relation one to the other along a laterally curved path having said predetermined radius of curvature at the median line of engagement of said slide fastener elements, and effecting permanent set of the fabric and rubber parts and permanent flattening of the rufiies in the one molded stringer by applying heat and pressure thereto for a limited yet sufiicient time while the molded united slide fastener is so retained upon said second molding surface.

9. Apparatus for making-a sealing slide fastener having spaced-apart laterally curved portions therein, said apparatus comprising a lower and an upper mold plate each having an elongated molding surface positionable with the molding surfaces in superimposed spaced relation one to the other in the closed condition of the mold plates, said molding surface of the lower mold plate having therein an upraised continuous straight separating rib extending centrally and longitudinally thereof and a pair of continuous straight channels along and contiguous to the two sides respectively of said rib to provide side areas in the lower molding surface extending laterally away from said straight channels, one of said side areas being flat throughout, the other side area having along and contiguous to the adjacent straight channel and undulating straight portion and a flat straight portion extending away from each end of the undulating straight portion toward the adjacent end of said lower molding surface, said undulating straight portion having a width equal to that of a stringer of a slide fastener to be molded and an actual length along said adjacent straight channel at least equal to the arcuate length of said stringer along a pre-formed laterally curved portion therein so as to underlie said laterally curved portion when it is in a straightened rufiled condition, said undulating straight'portion having interconnected substantially uniform undulations extending laterally thereof away from said adjacent straight channel across the entire width of such portion, the crests of said un dulations rising above and the hollows of said undulations falling below the level of the adjacent fiat straight portions with said crests gradually increasing in height and said hollows gradually increasing in depth away from said adjacent straight channel,rsaid molding surface of said upper mold plate having a pair of laterally spaced continuous straight molding grooves extending centrally and longitudinally therein for bridging said separating rib and directly overlying said straight channels in the lower molding surface and for molding sealing elements against the stringers of said slide fastener, and said molding surface of saidupper mold plate having side areas extending laterally away from the sides of said molding grooves corresponding "to said side areas in said lower molding surface, one of said side areas in the upper molding surface being flat throughout, and the other side area in the upper molding surface having both flat and undulating straight portions along the adjacent molding groove at positions corresponding to those of the flat and undulating straight portions the lower molding surface constructed and,

arranged for positioning inv complementary relation to said fiat and undulating straight portions in the lower molding surface in said closed condition of the mold plates. g 1 v 10. Apparatus for making va sealing slide fastener having spaced-apart laterally curved portions therein, said apparatus comprising a lower and an upper mold plate each having an elongated molding surface positionable with the molding surfaces in superimposed spaced relation one to the other in the closed condition of the mold plates, said molding surface of the lower mold plate having therein an upraised continuous straight separating rib extending centrally and longitudinally thereof and apair of continuous straight channels along and contiguous to the two sides respectively of said rib to provide side areas in the lower molding surface extending laterally away from, said straight channels, one of said side areas being flat throughout the other side area having along and contiguous to the adjacent straight channel apair of spaced-apart undulating straight portions and a flat straight portion extending between adjacent ends of the undulating straight portions and a fiat straight portion extending away from each of the other ends of the undulating straight portions toward the adjacent end of said lower molding surface, each undulating straight portion having a width equal to that of a stringer of a slide fastener to be molded and an actual length along said adjacent straight channel equal to the arcuate length'of said stringer along a pre-for'med laterally curved portion therein plus a predetermined additional length of said stringer adjacent thereto so as to underlie said laterally curved portion when it is in a straightened ruflied condition, each undulating straight portion having interconnected substantially uniform undulations extending laterally thereof away from said adjacent straight channel across the entire width of such portion, the crests of said undulations rising above and the hollows of said undulations falling below the level of the adjacent flat straight portions, said crests gradually increasing in height and said hollows gradually increasing in depth away from said adjacent straight channel to at least half said width of the portion and thereafter being of uniform height and depth respectively, said molding surface of said upper mold plate having a pair of laterally spaced continuous straight molding grooves each of generally triangular shape in crosssection with a connecting wall therebetween extending centrally and longitudinally therein for bridging said separating rib and directly overlying said straight channels in the lower molding surface and for molding sealing elements against the stringers of said slide fastener,

and said molding surface of said upper mold plate having side areas extending away from the sides of said molding grooves corresponding to said side areas in said lower molding surface, one of said side areas in the upper molding surface being flat throughout, and the other side area in the upper molding surface having both flat and undulating straight portions along the adjacent molding groove at positions corresponding to those of the said flat and undulating straight portions in the lower molding surface constructed and arranged for positioning in complementary relation to said flat and undulating straight portions in the lower molding surface in said closed condition of the mold plates.

11. Apparatus for making a sealing slide fastener having a laterally curved portion, said apparatus comprising a lower and an upper mold plate each having an elongated molding surface positionable with the mold- "ing surfaces in superimposed spaced relation one to the other in the closed condition of the mold plates, the lower molding surface having a side area and a continuous straight channel in said side area for accommodating and retaining slide fastener elements therein, said lower molding surfacehaving in said sidearea a flat straight portion extendingto an undulating straight portion with assets"? both portions disposed at and along said straight channel, the upper molding surface having a side area corresponding to that in said lower molding surface and a. continuous straight molding groove in the last said side area for forming a sealing element against a stringer of a slide fastener and positioned to overlie said channel in said closed condition of the mold plates, said upper molding surface having in said side area thereof a second flat straight portion extending to a second undulating straight portion with both portions disposed at and along said molding groove and at positions corresponding to those of said portions in the lower molding surface, and each said undulating straight portion having a plurality of interconnected undulations therein extending laterally across at least the major part of its width and the undulations in said second undulating straight portion being positionable in complementary relation to the undulations in the first said undulating straight portion in said closed condition of the mold plates so as to conform the, ruffied material of a stringer along a reach therein to the undulations in both said molding surfaces.

12. Apparatus for making a sealing slide fastener having a laterally curved portion, said apparatus comprising a lower and an upper mold plate each having an elongated molding surface positionable with the molding surfaces in superimposed spaced relation one to the other in ,the closed condition of the mold plates, the lower molding surfacev having laterally spaced-apart longitudinally-extending side areas and a pair of laterally spaced-apart longitudinal continuous straight channels therebetween for accommodating and retaining slide fastener elements therein, said lower molding surface having in one side area thereof a flat straight portion extending longitudinally to an undulating straight portion with both portions disposed at and along the adjacent straight channel, the upper molding surface having laterally spaced-apart longitudinally-extending side areas corresponding to those in said lower molding surface and a pair of laterally spaced-apart longitudinal continuous straight molding grooves therebetween for forming sealing elements against stringers of a slide fastener and positioned to overlie said channels in said closed condition of the mold plates, said upper molding surface having in one side area thereof a second flat straight portion extending longitudinally to a second undulating straight portion with both portions disposed at and along the adjacent molding groove and at positions correspond ing to those of said portions in the lower molding surface, the other said side areas of said molding surfaces respectively being flat throughout, and the two undulating straight portions being coextensive with a pro-determined length at least equal to the arcuate length of a pre-formed laterally curved portion of a stringer of the slide fastener and each having a plurality of interconnected undulations therein extending laterally across substantially its entire width, the undulations in said sec ond undulating straight portion being positionable in complementary relation to the undulations in the first said undulating straight portion in said closed condition of the mold plates so as to conform the ruffled material of said pre-formed laterally curved portion of a stringer in a straight condition to the undulations in both said molding surfaces.

13. Apparatus for making a sealing slide fastener having a laterally curved portion, said apparatus comprising a lower and an upper rigid molding surface positionable in superimposed, spaced relation in the closed condition of the apparatus, the lower molding surface including means extending in a straight path along the same for retaining slide fastener elements along said path when a stringer of a slide fastener is mounted on said lower molding surface, said lower molding surface including a flat straight portion at and to a side of said means and a straight stringer-shaping means connected to said portion and united with said lower molding surface and dis forming lateral undulations in rufiied material of said stringer along a reach therein, and said upper molding surface including means extending in a straight path along the same for molding a sealing element against said stringer, a second flat straight portion to a side of the molding means for overlying the first said fiat straight portion and a second straight stringer-shaping means to said side of the molding means for overlying the first said straight stringer-shaping means in complementary relation thereto in said closed condition of the apparatus.

14. Apparatus for changing permanently a laterally curved portion of a closed molded sealing slide fastener from its molded-in radius of curvature to a final differ ent radius of curvature, said apparatus comprising an upper and a lower mold plate each having a molding surface positionable with the molding surfaces in superimposed predetermined spaced-apart relation in the closed condition of the mold plates, said lower mold plate having in its molding surface means for engaging the engaged sealing elements of the laterally curved portion in the closed molded slide fastener in a manner to retain the engaged sealing elements along an arcuate centerline having predetermined length and a radius of curvature different than that of the arcuate centerline of the said laterally curved portion, an arcuate flat portion of substantially uniform width in said lower molding surface contiguous to each side of the engaging means to provide a pair of arcuate flat portions of pre-determined length in radially spaced-apart concentric relation for underlying and supporting thereon the radially inner and outer attaching margins in said laterally curved portion of the closed molded slide fastener, and registering means at the convex margin of the radially outer fiat portion and at the concave margin of the radially inner fiat portion in said lower molding surface, and said upper mold plate having in its molding surface means for engaging and retaining the exposed parts of the engaged slide fastener elements in'the laterally curved portion of the closed molded slide fastener along an arcuate centerline of pre-determined length and a radius of curvature corresponding to that of the first said centerline, a second pair of arcuate flat portions of predetermined length and substantially uniform width contiguous to the sides of the last said means and arranged in radially spaced-apart concentric relation one to the other for directly overlying said pair of arcuate flat portions in said lower molding surface, and means in the upper molding surface at the convex margin of the radially outer fiat portion therein and at the concave margin of the radially inner flat portion therein engaging said registering means in the closed condition of said mold plates so as to maintain the molding surfaces in said superimposed pro-determined spacedapart relation.

15. Apparatus for changing permanently a laterally curved portion of a closed molded sealing slide fastener from its molded-in radius of curvature to a final different radius of curvature, said apparatus comprising an upper and a lower mold plate each having a molding surface positionable with the molding surfaces in superirnposed pre-determined spaced-apart relation in the closed condition of the mold plates, said lower mold plate having in its molding surface a forming groove of sufficient dimensions and a shape for receiving snugly therein the engaged sealing elements of the laterally curved portion in the closed molded slide fastener, said forming groove extending'in the lower molding surface along a centerline having pro-determined arcuate length and a radius of curvature different than that of the arcuate centerline of said laterally curved portion, an arcuate flat portion of substantially uniform width extending contiguous to and coextensively along each side of said forming groove to provide a pair of arcuate flat portions of pro-deter mined length in radially spaced-apart concentric relation 21 for underlying and supporting thereon the radially inner and outer attaching margins in said laterally curved portion of the closed molded slide fastener, and registering means along the convex margin of the radially outer flat portion and along the concave margin of the radially inner flat portion in said lower molding surface, and said upper mold plate having in its molding surface a shallow recess of sufficient dimensions and a shape to receive snugly the exposed parts of the engaged slide fastener elements in the laterally curved portion of the closed molded slide fastener and extending along an arcuate centerline of predetermined length and a radius of curvature corresponding to that of said forming groove, a second pair of arcuate fiat portions of pro-determined 22 tiguously along the sides of said shallow recess in radial- 1y spaced-apart concentric relation one to the other for directly overlying said pair of arcuate fiat portions in said lower molding surface, and means in the upper molding surface along the convex margin of the radially outer flat portion therein and along the concave margin of the radially inner flat portion therein engaging said registering means in the closed condition of said mold plates so as to maintain the molding surfaces in said superim- 10 posed Ire-determined spaced-apart relation.

length and substantially uniform width extending con- 15 Krupp Mar. 20, 1951 Soave June 25, 1957 

